Detection of icaAD gene and biofilm formation in staphylococcus aureus isolates from wound infections

Wound infections are a common cause of staphylococcal infections. An ability of S.aureus is to adhere and form biofilm on host surfaces. Biofilm is an exopolysaccharide, a slime matrix around multiple layers of cells and is mediated by expression of the icaADBC operon. The present study evaluated the biofilm forming capacity and the presence of icaAD gene among S.aureus isolated from wound infections. Slime production assay was performed by cultivation on Congo Red Agar plate. In addition, Quantitative biofilm formation determined by microtiter plate assay PCR method used for detection of icaAD gene. Fifty strains were identified, 54% of the isolates produced black colonies on CRA plate, 52% were positive biofilm forming, and all strains carried the icaAD gene. Regarding the ability of S.aureus to form biofilms helps the bacterium to survive hostile environments within the host, suggests that biofilm production is a risk factor for infection. It is important in rapid diagnosis and treatment biofilm forming strains, because biofilm formation may lead to increased antimicrobial resistance and create a significant impediment to wound healing

[ distribution of Vibrio cholerae from the surface waters of Golestan province]

Vibrio species are oxidase positive, gram negative bacilli that predominantly reside in surface waters such as lakes, rivers. They cause predominantly intestinal diseases as well as a few extra-intestinal complications. Vibrio-related diseases often rise during natural disasters such as floods. Vibrio cholerae cause cholera in humans. In this study, the occurance of Vibrio cholerae in the surface waters of Golestan province, was investigated. The APW and TCBS agar culture media were used for primary isolation of Vibrio cholerae and the exact species identification were done by performing the following tests; oxidase reaction, growth in 0%, 1%, 3%, 6% salt solution, lysine and ornithine decarboxylase, Arginine dehydrolase, ONPG and VP test, simmon citrate, bile esculin, indole, CAMP reaction, string test and specific antisera to V.cholerae 01. to confirm the findings, the special antiserum Ogawa and Inaba, were used. We were able to isolate 42 Vibrio spp. from a total of 54 water samples collected. The species included 35 non-01 V.cholerae [84.2%], 2 V.mimicus [2.63%] and 5 V.cholerae 01 [13.1%] isolat. This study confirmed the existence of Vibrio cholerae 01 in 70% of samples from surface waters of Golestan province